summaryrefslogtreecommitdiffstats
path: root/doc/src/snippets/reading-selections/model.cpp
blob: 8df8ecc1598c1acac3046b1a88ee5e6542d3e738 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

/*
    model.cpp

    Provides a table model for use in various examples.
*/

#include <QtGui>

#include "model.h"

/*!
    Constructs a table model with at least one row and one column.
*/

TableModel::TableModel(int rows, int columns, QObject *parent)
    : QAbstractTableModel(parent)
{
    QStringList newList;

    for (int column = 0; column < qMax(1, columns); ++column) {
        newList.append("");
    }

    for (int row = 0; row < qMax(1, rows); ++row) {
        rowList.append(newList);
    }
}


/*!
    Returns the number of items in the row list as the number of rows
    in the model.
*/

int TableModel::rowCount(const QModelIndex &/*parent*/) const
{
    return rowList.size();
}

/*!
    Returns the number of items in the first list item as the number of
    columns in the model. All rows should have the same number of columns.
*/

int TableModel::columnCount(const QModelIndex &/*parent*/) const
{
    return rowList[0].size();
}

/*!
    Returns an appropriate value for the requested data.
    If the view requests an invalid index, an invalid variant is returned.
    Any valid index that corresponds to a string in the list causes that
    string to be returned for the display role; otherwise an invalid variant
    is returned.
*/

QVariant TableModel::data(const QModelIndex &index, int role) const
{
    if (!index.isValid())
        return QVariant();

    if (role == Qt::DisplayRole)
        return rowList[index.row()][index.column()];
    else
        return QVariant();
}

/*!
    Returns the appropriate header string depending on the orientation of
    the header and the section. If anything other than the display role is
    requested, we return an invalid variant.
*/

QVariant TableModel::headerData(int section, Qt::Orientation orientation,
                                int role) const
{
    if (role != Qt::DisplayRole)
        return QVariant();

    if (orientation == Qt::Horizontal)
        return QString("Column %1").arg(section);
    else
        return QString("Row %1").arg(section);
}

/*!
    Returns an appropriate value for the item's flags. Valid items are
    enabled, selectable, and editable.
*/

Qt::ItemFlags TableModel::flags(const QModelIndex &index) const
{
    if (!index.isValid())
        return Qt::ItemIsEnabled;

    return Qt::ItemIsEnabled | Qt::ItemIsSelectable;
}

/*!
    Changes an item in the model, but only if the following conditions
    are met:

    * The index supplied is valid.
    * The role associated with editing text is specified.

    The dataChanged() signal is emitted if the item is changed.
*/

bool TableModel::setData(const QModelIndex &index,
                         const QVariant &value, int role)
{
    if (!index.isValid() || role != Qt::EditRole)
        return false;

    rowList[index.row()][index.column()] = value.toString();
    emit dataChanged(index, index);
    return true;
}

/*!
    Inserts a number of rows into the model at the specified position.
*/

bool TableModel::insertRows(int position, int rows, const QModelIndex &parent)
{
    int columns = columnCount();
    beginInsertRows(parent, position, position + rows - 1);

    for (int row = 0; row < rows; ++row) {
        QStringList items;
        for (int column = 0; column < columns; ++column)
            items.append("");
        rowList.insert(position, items);
    }

    endInsertRows();
    return true;
}

/*!
    Inserts a number of columns into the model at the specified position.
    Each entry in the list is extended in turn with the required number of
    empty strings.
*/

bool TableModel::insertColumns(int position, int columns,
                               const QModelIndex &parent)
{
    int rows = rowCount();
    beginInsertColumns(parent, position, position + columns - 1);

    for (int row = 0; row < rows; ++row) {
        for (int column = position; column < columns; ++column) {
            rowList[row].insert(position, "");
        }
    }

    endInsertColumns();
    return true;
}

/*!
    Removes a number of rows from the model at the specified position.
*/

bool TableModel::removeRows(int position, int rows, const QModelIndex &parent)
{
    beginRemoveRows(parent, position, position + rows - 1);

    for (int row = 0; row < rows; ++row) {
        rowList.removeAt(position);
    }

    endRemoveRows();
    return true;
}

/*!
    Removes a number of columns from the model at the specified position.
    Each row is shortened by the number of columns specified.
*/

bool TableModel::removeColumns(int position, int columns,
                               const QModelIndex &parent)
{
    int rows = rowCount();
    beginRemoveColumns(parent, position, position + columns - 1);

    for (int row = 0; row < rows; ++row) {
        for (int column = 0; column < columns; ++column) {
            rowList[row].removeAt(position);
        }
    }

    endRemoveColumns();
    return true;
}